Background
Epigenetic alterations, including post-translational modification of histone tails by methylation may play an important role in carcinogenesis.
Objective
The aim was to evaluate the global histone H3K27 dimethylation (H3K27me2) levels in bladder cancer (BC) and to compare these levels in different types and stages of BC.
Materials and Methods
Venous blood from 45 BC patients and 45 apparently healthy controls was used. The two risk factors such as infection and smoking were investigated. Histone extraction was done and used to determine the global levels of H3K27 dimethylation.
Results
Global level of H3K27 dimethylation was significantly lower in BC patients than in healthy controls. We observed a negative correlation between histone dimethylation levels and the smoking state (both in patients and controls). Receiver operating characteristic curve showed that histone H3K27me2 at a cut-off point less than 49.68 ng/μl has 69% sensitivity and 64.5% specificity for the prediction of BC with an area under the curve of 0.67 ( = 0.001). However, there was no statistically significant difference in H3K27me2 levels as regards history of infection ( = 0.6), histopathological types ( = 0.3), and the stages of cancer ( = 0.8).
Conclusion
The global histone H3K27 dimethylation may substantiate the potential to improve the detection of early-stage urinary bladder carcinoma. Also, the decreased level of histone H3K27me2 in smokers (either patients or controls) could be one entity that explain smoking as a risk factor for BC.